This invention relates to optical fibers and more particularly to a method for making a device for attenuating light signals coupled from one optical fiber to another.
In the prior art, optical attenuators are provided as separate piece parts which are inserted between the ends of two optical fibers by means of mechanical coupling devices. Inserting such an optical attenuator into a system adds not only the attenuator itself but also the mechanical coupling devices. It is well known that system reliability is reduced by any increase in the number of separate components, or devices, used in the system. Thus the insertion of the optical attenuator plus the coupling devices not only increases optical loss but also reduces system reliability.
For an undersea optical fiber transmission system requiring very high reliability, it is desirable to insert an optical attenuator in between the ends of two optical fibers by using the lowest possible number of separate parts to retain high reliability while increasing optical loss. Thus there is a problem in inserting an optical attenuator between the ends of two optical fibers without reducing reliability.